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Vomiting and diarrhea in a baby or child: fluids, and when to call
For anyone looking after a baby or child who is throwing up or has diarrhea: a parent, a grandparent, a sitter, at any hour. This page passes on, by name, what the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) and the Centers for Disease Control and Prevention (CDC) say: the signs of dehydration, giving liquid in small sips, what the pages say to give and where they differ, feeding a baby, what to eat, why diarrhea medicine is not for children unless a doctor says so, how to keep it from spreading, and the signs that mean a call to the doctor. It builds the questions to ask. Take only what you need tonight.
Right now
- A child who cannot be woken, is limp or does not respond, is struggling to breathe, or has a seizure? Call 911. This line is ours: none of the pages we pass on names 911.
- A baby younger than 12 months with diarrhea? NIDDK says to seek a doctor’s help right away. It says the same for a child with diarrhea who was born prematurely or has a history of other medical conditions.
- Signs of dehydration? NIDDK says infants, toddlers, and young children with dehydration may have no wet diapers for 3 hours or more, no tears when crying, a sunken soft spot in the skull, and drowsiness; its list also has a dry mouth and sunken eyes or cheeks. NIDDK says anyone with signs or symptoms of dehydration should see a doctor right away, and that a child with symptoms of dehydration can die within a day if left untreated.
- Talk with a doctor right away, NIDDK says, for a change in mental state such as irritability or lack of energy; frequent vomiting; severe pain in the abdomen or rectum; stools that are black and tarry or contain red blood or pus; diarrhea lasting more than a day; any fever in an infant, or a high fever in an older child; or an infant refusing to eat or drink anything for longer than a few hours.
- Give liquid in small sips. NIDDK says: if vomiting is a problem, try sipping small amounts of clear liquids. It says to seek a doctor’s help right away if the child can’t drink enough liquids to prevent dehydration.
- Do not give a child over-the-counter medicine for diarrhea without talking with a doctor first. NIDDK says these medicines can be unsafe for infants and children.
- Could your child have swallowed something? See When it might be a poisoning. Pointing there is ours.
If you cannot reach a provider and you are frightened for your child, go to an emergency room or call 911. That line is ours. This page is not for emergencies.
Changed on October 10, 2026. This box first gave lines from encyclopedia articles we should not have used. They are out; what is here now is NIDDK’s, or marked ours. The note at the bottom of the page says what changed.
More help
- A fever with it: Fever in a baby or child: when to call, and what helps.
- Something a child may have swallowed: When it might be a poisoning. First aid: First aid: what do you see?
- Counting wet and dirty diapers and feeds: Baby log. Writing down what happened and when: Symptom diary.
- Breastfeeding through an illness: Breastfeeding: when it hurts, or you’re not sure it’s working.
- A baby who will not stop crying: Crying baby: when the crying won’t stop.
- For a visit: Get ready for your appointment. No insurance: When you need a doctor and can’t pay.
- A newborn at home: Pregnant, or with a new baby.
- All our free tools.
An upset stomach, and not sure this is the right page? The pages on this site for throwing up, diarrhea, heartburn and constipation, on one list.
Looking after a baby or child? The pages on this site for a baby or child, on one list.
Other guides on this site that go with this page
Free to read. We chose these ourselves; no professional did. Each guide was written with AI and has not been reviewed by a professional. They are general information, not advice.
- Hirschsprung disease (a birth defect of the intestine): the signs, the tests, surgery, and after: Hirschsprung disease, a birth defect of the intestine: the signs in a newborn and an older child, enterocolitis, the tests, surgery, and after.
- Reflux in babies (spitting up, GER and GERD): what is normal, the warning signs, and the treatment: a baby who spits up a lot (reflux, GER and GERD): what is normal and how common, the signs that mean calling a doctor right away, the tests, the treatment, and changes to feeding.
- Acid reflux in children and teens (heartburn, regurgitation, GER and GERD): the signs, the tests, and the treatment: a child or teen with heartburn or food coming back up (acid reflux, GER and GERD): who gets it, the complications, the signs that mean calling a doctor right away, the tests, the treatment, and food and weight.
- Hemolytic uremic syndrome (HUS) in children: the signs, when to get care, the hospital, and preventing it: hemolytic uremic syndrome, HUS (a child with bloody diarrhea from E. coli, then paleness, tiredness, bruises, swelling or less urine): what it is, the causes, when to seek immediate care, the tests, the hospital and dialysis, getting better, and preventing it.
- Chronic diarrhea in children: the signs, dehydration and when to get care right away, the common causes, how doctors find the cause, treatment, and food: a baby, a child or a teen with loose, watery stools for weeks: the signs, dehydration and when to get care right away, the common causes (infections, celiac disease, toddler’s diarrhea, food allergies and intolerances, IBS, IBD), the tests, treatment and food.
- Diarrhea: what it is, the causes, staying hydrated, what to eat, the tests, treatment, and when to get help: diarrhea in adults and children: the causes, what to drink and eat, the tests, treatment, and when to get help.
This page and its wording were written with AI (Claude) for Scarlet Beast (our AI policy). No doctor, nurse or pharmacist has reviewed it. Changed on October 10, 2026. When this guide was published on October 9, most of it passed on five articles of a medical encyclopedia that is licensed text; its publisher’s notice does not allow that reuse, including by AI. We had decided not to use such articles and then did. That was our mistake. Every line from them is out. What the page passes on now, read on October 9 and 10, 2026, every page in English and in Spanish: six pages of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the National Institutes of Health: Symptoms & Causes, Treatment, and Eating, Diet, & Nutrition for Diarrhea (each says “Last Reviewed September 2024”), and the same three pages for Viral Gastroenteritis (“Stomach Flu”) (each says “Last Reviewed May 2018”, so they are older, and the page says so when it uses them); and three pages of the Centers for Disease Control and Prevention (CDC): About Norovirus (April 24, 2024), How to Prevent Norovirus (reviewed January 13, 2025) and About Rotavirus (April 22, 2024). The CDC pages are written for all ages, and the page says so where it matters. Where the sources differ, the page gives each: what to give a child to drink is an oral rehydration solution on NIDDK’s older page, and plenty of water as well as oral rehydration solutions, broths and sports drinks on its newer one, while CDC says sports drinks may not replace important nutrients and minerals; the older NIDDK page says some probiotics may help shorten a case of diarrhea, and the newer one says many doctors and professional societies don’t believe the evidence supports their use; the newer page says to seek a doctor’s help right away for a child with diarrhea who is younger than 12 months, where the older one says “is an infant”; NIDDK says to use hand sanitizer when there is no soap and water, and CDC says hand sanitizer does not work well against norovirus; and the two NIDDK pages word the timing of the rotavirus vaccine differently. What is gone because no page we may pass on says it: every amount of liquid, by the spoonful or the ounce, and how many minutes apart; a line for babies under 3 months (the pages say younger than 12 months); 6 hours and 8 hours without a wet diaper or urine (the pages say 3 hours or more); how to tell diarrhea from a baby’s usual stools; how to mix formula; diaper rash; lists of mild foods and of foods to avoid; frozen pops, gelatin, juice and water by itself; salt tablets; two lists of signs for 911 or an emergency room, including blood or dark material in vomit, passing out, and a fever number; counts of stools; and a line about COVID-19. For those, ask your child’s provider; if you see something that frightens you, call. What is marked “ours” is our own, including every line that names 911: none of the pages names it. What we left out: every brand name (the older NIDDK page names oral rehydration solutions, diarrhea medicines and the rotavirus vaccines); the name and amount of every medicine; NIDDK’s lists and time limits for adults; alcoholic drinks, which are on NIDDK’s list for all ages; making a rehydration solution at home, which NIDDK mentions for adults; long-lasting (chronic) diarrhea and its causes; food poisoning and travel as their own subjects; shellfish and food safety on CDC’s pages; the tests done at a visit; reflux and spitting up in babies. We called no number. It saves nothing and loads no tracking.